Mixing device



May 11 1926.

J. W. SMITH MIXING DEVICE Filed Oct.

Wifn 6.956s

invenfor L.) r cfi M an w w J i z CMQU. J/

Patented May 11 1926.

V'TUNITED STATES some WILLIAM sm'm, or sxnacusn, New Yonx.

mxmo DEVICE.

Application filed October 11, 1922. Serial No. 593,933

This invention relatesto devices for mixing a variety of flowable materials, for instance, fuel mixtures, though it isv noted that the invention is not limited to fuel mixing,

nor in some respects to fuels or mixing.

One object of the invention is to provide an improved device of this kind in which 'the various materials are intimately mixed at the same time that they are being transported.

Another object is to provide a device of this kind in which the miscible materials are subjected to some or all of a lar e number of actions such as shocks, co lisions, changes of directions, diversions, outward and inward movements, rotations, divisions and recombinations.

Another object of the invention is to provide an improved device of this kind in which any number of various gaseous, liquid reagents or solid reagents or mixtures thereof may be intimately mixed. The solid and liquid materials may be finely divided "before or after the mixing is cbmmenced.

Another object-pf the invention is to provide an improved mixture carrying within itself all ingredients for complete combustion or other reactions. A fuel in accordance with this invention is suitable for fur- 39 naces, blast furnaces, burners, automobile or other internal combustion engines and other purposes and may be made by the above mentioned apparatus, though the invention is not so limited. For example, a fuel in accordance with this invention may comprise a mixture of the l3Y7PIOd11Cl] gases of blast and coke furnaces, air and divided coke or coal or any two of these.

A leading object of the present invention is to furnish an improved means or apparatus, for unifyingthe admixture of diverse materials which form and are carried along in a flowing stream; also, to incorporate together a plurality of streams of dive'rse but miscible materials to form thereof a single stream having throughout a highly uniform character as regards admixture and quality. The purpose of the present improvements is not merely to mix, but to effect a uniform distribution in the stream of the materials comprising this stream, applicants apparatus being intended for associating the materials into a stream which shallas a result of a gradually eflected associating processflow along in a non-segregating condition,

and thus have a uniformity of admixture throu bout the cross-sectional area of the conduit where this delivers the stream to the furnace chamber.

"Thus the stream is successively treated in a manner thereby to intermix the contents thereof to a minimum amount while progressively developing the uniformity of admixture or distribution, this being incompatible with any excessive or violent rotative action, since such excessive or violent rotative action is chiefly separative in its nature and efl'ects, this fact being well shown by the common use of this form of rotative means in oil separators, and in a variety of analogous classes. In the present invention the rotative feature is only employed to turn over slowly the forming stream for thereby overcoming the eiiect of gravity, and thus continuously to restore to the central column (stream) such materials as otherwise would tend to form a sedimentary layer along the bottom of the conduit.

The present improvements are applicable to the treatment of a considerable variety of materials, uses, of which one of the most important is deemed to be the incorporating of finely comminuted solids and liquids in streams of air or other gases. Accordingly, for the purposes of this present application, the invention is herein described in connection. with drawings of simple but typical forms of apparatus which may be employed for eilecting or improving the admixture of finely comminuted coal in a flowing stream of air, or for similarly treating an admixture of comminuted or vaporized oil (or of other vapor or combustible liquid) and a stream of air or other gas, particularly one having a relatively low specific gravity. This apparatus and method are particularly eilicient for ingredients having widely different specific gravities, such ingredients being very imperfectly miscible by methods heretofore known. in practice, of course, the apparatus should be so proportioned, and be of such dimensions, as to be'suitable for the service required in any particular in stance.

Another object of the invention is to provide in an apparatus or device of this kind means to give to the stream rotations or alternately opposite rotations about the axis of the conduit.

and to a wide range of special ltlil Other objects of the invention are to improve generally the simplicity and efficiency of such devices and to provide a device or apparatus of this land which is durable economical to manufacture and operate an divide liquid and finely divided solids or Ether materials intoand through said conuit.

Other objects of the invention will appear as the description proceeds; and while herein details i of the invention are described, the invention is not limited to these, since many and various changes may be made without departing from the spirit of the invention or exceeding the scope of .the appended claims. a

- In the accompanying drawing, showing by Fig. 3 is a transverse sectional view, part-' ly in elevation, taken onthe line 3-3 of Fig. 2 looking in the direction of the arrow of said line;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a longitudinal vertical sectional view, partly in elevation of a portion of another form of mixing section;

Fig. 6 is a transverse sectional view, part- 1 in elevation, taken on the line 55 of h ig. 4 looking in the direction of the arrow of said line; and

Fig. 7 is a diagrammatic view showing paths of portions of the mixture.

My improved apparatus of Figs. 1 to 4 comprises a stream unifying conduit 10, for transmitting admixtures of diverse flowable material, comprising a tubular sections or lengt s 11 and 12 each provided with outer transverse end-flanges 14, 15, at the ends. Certain of said sections 12 are longer than the remaining sections, the shorter sections 12 comprising removable upper halves and lower halves all provided with horizontal supporting and connecting flan cs 18 and 19 (Fig. 3) extending to the end anges. Supportin brackets 20 having a base 21 and'upturne arms 22 engaging under and secured by bolts 23 to the lowest of said supporting flanges 19 support the conduit as a whole. An upturned dislurality of alined,

said mem rs is formed with a plurality of inwardly and forwardly pointing fin ers or projections or incisor blades33, 34, Figs. 2 and 4 of helical form terminating a suitable distance between the center and circumferenceof the member and having flatfoni,

ward faces 35 exposed to the oncoming m1x ture and serving to press inwardly portions of the stream. Said projections together form a serrated cone or Venturi-shaped member having therein a series of intermediate interruptions 36 forming passages for non- .continuous outer portions of the stream.

When it is desired to remove the members 26, "it 1s only necessary first to remove the bolts 23 and 30 and the upper halves of section 11. 1 The blades 33, 34 of each member preferably oppose the space between adjacent blades of a succeeding member.

The blades 33, '34, of each of said sections are gradually increasingly inclined (Fig. 4)

on their own axes in the same direction to give a rotary motion to the .stream, the

blades of adjacent sections being oppositely inclined to give to the stream opposite rotations about the axis of the conduit as the blades of successive members may oppose one another, and in such case, the blade 33 as shown in solid lines in Fig. 4 is inclined 1n one direction, while the blade 34 on the other section shown in dotted lines is inclined in the opposite direction. Several adjacent sections may be inclined in the same direction, or the sections may be alternately oppositely inclined.

The helical form of the blades permits the blades to impart a rotary motion to the stream, while the blades themselves are stati onary and need not rotate. The stationary blade is considered very superior to rotary blades. but the invention is not limited to non-rotary mixing members, nor to helical or laterally inclined forms. Said blades or pro'ections also cooperate for intermittenty rst accelerating and next retarding the flow of the stream as a given part thereof passes along the conduit, and also subject 1 the outer zone of the stream to a concurrent subdivision and a following reformation, thereby, while intermixing t e mass of the stream, increasing the normal excess in the speed of fiowage of the central part rela-.

tively to the outer portion, thus mixing theas a crown mixer.

As shown in Figs. 2 and 3, the-.bladesbt are substantially triangular 1n shape, with theirbases disposed in a continued unintenrupted line in the inner periphery of the conduit 12, and the apices of the blades 34 define the central opening through the mixing member. From Fig. 2 it willalso appear that theinner faces of the blades 34 form continued uninterrupted surfaces with the inner surface of the conduit 12, or in other words, form uninterrupted continuations of the inner surface of the conduit 12 which gradually incline from the inner surface of the conduit 12. By means ofthis relation of the blades with'the conduit, the

' flow of mixing material will freely move bil from the inner surface, of the conduit 12 to the inner faces of the blades 34 without undue retardation at the inner surface of the conduit 12, and the flow ofmixing material adjacent to the inner surface of the conduit 12 will be controlled throughout by the blades 34 before passing beyond the blades 34 to the inner surface of the conduit beyond the blades 34.

At the inlet end of the mixing conduit is a combining section 40 having a round discharge portion, comprising a pair of diametrically separated upper and lower channels ll and 42 and a pair of round upper and lower gas and air inlet conduits 43 and id respectively merging into and feeding said channels. An air impeller 25, is connected by a pipe 46, and furnishes air under pressure to the lower conduit 44, and a liquid inlet pipe at? entering the air pipe has a forwardly turned injector-like nozzle 48, whereby liquid may be imparted to the stream of air.

A, gas-tight feed device 5Ghaving a gastight removable cover 51 is provided with a feed drum 53 provided with pockets 54 which receive pd'rtions of finely divided coke or coal alone or mixed or other material or mixture through the regulating valve gate 55 and drop them into a gas-tight hopper 57 in turn feeding into the upturned end 58 of the pipe 59 leading to the upper conduit 43. An annular pipe 60 communicating with a gas feed pipe 61, is disposed in the upper part of said hopper and has downwardly disposed openings 62 whereby the gas is fed into said hopper 57 as the divided material is fed thereto. This feed device is fully described in United States Patent No. 984,254, to C. E. Akel'ey, is here shown only by way of example, the invention being not so limited.

of the gas and dischar ed at the u Said gas and the powdered material mixed therewith are carried along by the pressure per part of said combining mem er 40 into t e stream of air from the lower pipe 44, the reby to supply the air and the gas mixture to the unifying conduit for intimate mixing. It will'be remembered that when a fullsize stream flows along normally in that part of a conduit which has a uniform sectional area, there is naturally (in accordance with well-known physical laws) a higher rate of movement in the central-zone of the stream than at or near the outer surface of the stream. In the present method, the resistance afforded as against the forward movement of the outer part of said stream, by the concentric series of incisor devices or blades, operates to retard this movement, while the restriction of the conduit tends to centralize the fiowage and thus accelerate the forward velocity of the central portion of the stream, thereby producing a greater than normal difference in' rate of flow between the forward velocities of the inner and outer portions, respectively, of the flowing materials.

in the form of invention shown in Figs. 5 and 6 the stream unifying conduit for transmitting the admixtures of diverse fiowable material comprises a plurality of alined tubular'sections l2 eachprovided with an outer transverse end-flange 15 and an annular recess 17 at each end; and the mixing members 28'" and 28 are made of sheet metal and each has its outer part engaged between, or in, the adjacent annular recesses 17'. Said members are formed preferably by a stamping process with a plurality of inwardly and forwardly pointing helical blades 33 having the same general form and function as described of the form of Figs. 2 to d while the mixing members 28 are shown as stampings and the members 28 (Fig. 2) are shown as castings, the invention is not limited either to stampings or cast ings. As shown in Fig. 5, the plates 34' of section 28* are twisted in the opposite direction to the twist of the blades 33' of the succeeding section 28 to form helical con formations, and in addition therewith the blades 34 oppose the spaces formed between the blades 33 of the succeeding member 28'.

The operation of the apparatus is simple, and obvious from the foregoing. Finely divided material, for instance, coal or coke or a mixture of the two, is placed in the feed device 50 and the cover placed on air tight. The impeller 45 feeds air into and through the lower channel 42. while the pressure in the gas feed pipe 61 carries the fuel gas down through the hopper 57 and through thempper channel 41. Rotation of the drum 53 drops the finely divided'solid fuel into the fuel gas, while the nozzle 48 injects the liquid fuel into the air. From the combining member 40 the ingredients are carr ed forward to the mixing conduit 10. Where a mixture of gases are fed to the gas feed pipe 61, these may be intimately mixed and unified by a mixing conduit similar to the conduit. 10.

This apparatus may be used for mixing.

materials other than fuels and is suitable for mixing almost any flowable materials. If a fuel mixture is to be made different ingredients or a greater or smaller number of ingredients may be used. A particular advantage of the invention is that t various ingredients may be so proportioned and mixed that the fuel is entirely self supporting, that is, contains its own combustion supporting elements.

As the mixture passes the members 28 or 28 it is given rotary motions in alternately movement, and relative longitudinal mixing.

illustrated diagrammatically in Fig.

These movements result in a very intimate homogeneous mixture and a highly eflicient fuel and fuel reaction.

The mixing conduit is designed to bring about a large number of shocks, collisions and changes of direction to the mixture which is found to aid greatly in thorough mixing. This may be as shown diagrammatically in Fig. 7, wherein the mixture of. flowable materials is transmitted in a stream indicated by the dotted lines 65, 66,

bringing the outer portions of the mixture into angular collision, as at 67, with fixed serrated structure or projections 28, thereby diverting inwardly portions of the outer zone to bring them in collision, as at 69, with each other and the central portion of the stream, thereby crossing and again diverting' and diverging the collided portions outwardly, as at 70, and bringing portions of the again diverted material into abrupt collision with fixed structure 28 of the next mixing member thereby to divide and again abruptly change the direction portions thereof, as at 71, portions 72 passing through and assuming a direction approximating parallel to the conduit.

In my copending application, Serial No. 99,885 filed April 5, 1926, the embodiirgent 1s further illustrated and described. I claim: 1, In a device of the character. described,

the combination with a conduit, of a mixtion of the blades relative to the dome formed thereby causing the deflection of the stream portionof the material engaging the blades'to bedefiected out of the dome, the bases of the blades forming a continuous unlnterrupted line in the inner surface of the conduit so as to prevent the immediate passage of the material beyond the mixing member without first being engaged and directedby said blades.

2. In a device of the character described, the combination with a conduit, of a plurality of mixing members, each mixing member havin a plurality-of imperforate triangular bla es extending inwardly from the periphery of said" conduit and inclined thereto to form a dome havin a central opening defined by the apices o the blades for the passage of a stream portion of the material being mixed, the inclination of the blades relative t2) the dome formed thereby causin the deflection of the stream portion of t a material engaging the blades to be deflected out of the dome, the bases of the blades of each member being disposed in a continued uninterru ted line at the inner surface of 'the con uit, the successive members extending in the same direction, the discharging end of the blades of each member being spaced from the receiving endof the blades of the successive member so that the material being mixed when discharged from one member will be received by the succeeding member to redirect the' particles of the material being mixed into the central portion of the main stream portion.

3. In a device of the character described, the combination with a conduit, of a .plu'- rality of mixing members, each mixing member having a plurality of imperforate triangular blades extending inwardly from the periphery of said conduit and inclined thereto to form a dome havin a central opening defined by the apices of the blades for the passage of a stream portion of the material being mixed, the inclination of the blades relative to the dome formed thereby causing the deflection of the stream portion of the material engaging the blades to be deflected out of the dome, the bases of the blades of each member being disposed in a continued uninterrupted line at the inner surface of the conduit, the successive members extending in the same direction, the discharging end of the blades of each memher being spaced from the receiving end of the blades of the successive member so that the material being mixed when discharged from one member will be received by the succeeding member to redirect the particles of the material being mixed into the central portion of the main stream portion', and the inner faces of the blades forming continued uninterruptedsurfaces with the inner surface of the conduit.

4. In a device of the character described, the combination with a conduit, of a plu- 1'alit of mixing members, each mixing member having a plurality of imperforate triangular blades extending inwardly from the periphery of said conduit and inclined thereto to form a dome having a central opening defined by the apices of the blades for the passage of a stream portion of the material being mixed, the inclination of the blades relative to the dome formed thereby causing the deflection of the stream portion of the material engaging the blades to be deflected out of the dome, the bases of the blades of each member being disposed in a continued uninterrupted line at the inner surface of the conduit, the successive members extending in the same direction, the discharging end of the blades of each memher being spaced from the receiving end of the blades of the successive member so that the material being mixed when discharged from one member will be received by the succeeding member to redirect the particles of the material being mixed into the central portion of the main stream portion, and the member.

JOHN WILLIAM SMITH. 

